REPORTING ENTITY (Detail)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Entity Information [Line Items]
Percentage of total premium and services revenues derived from contracts with the federal government	81.00%	79.00%	75.00%
Florida
Entity Information [Line Items]
Percentage of premiums and services revenue related to contracts with CMS for Medicare Advantage members in Florida	15.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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